German Patent Specification 1,571,070 proposes an apparatus having a frame on which a door to be clad with synthetic plastic foil is supported; that side of the door which is to be clad faces downwardly. A supply roll of the foil is turnably mounted between two arms which can be pivoted with it in direction upwardly and downwardly of the frame.
Visual observation of the proper positioning of the foil on the door is, at best, difficult because the side being clad faces downwardly. Even more importantly, stretching of the foil to tighten it in transverse direction of the door, cannot be visually observed. Thus, assuming that the foil has a printed, embossed or otherwise applied pattern, it is very difficult and tedious to determine whether the foil is properly positioned on the door in such a manner that the pattern parallels the longitudinal door edges. Actually, there is no satisfactory way of exercising such control, except to turn over the door; evidently, this requires substantial additional work and increases the manufacturing cost.
The foil being applied to the door must be tensioned to assure that it is smooth and wrinkle-free. The prior-art proposal requires that the tension be maintained, during the application process, by pivoting the rather heavy supply roll upwardly to a position above the door, an operation which either requires more than one operator or power-assist devices which increase the cost of the machine. For the next-following cladding operation the supply must then be returned again to its lower position. Moreover, the desired degree of stretch for the foil, imparted thereto by the position of the supply roll, can at best be controlled only haphazardly, so that non-uniform stretching results in a non-uniform product surface.
The prior-art proposal is therefore not satisfactory and further improvements are desirable.